With recent miniaturization (compactness) of cameras, miniaturization of built-in electronic flushes also rapidly proceeds, and the problem of underexposure caused by insufficient quantity of light is pointed out in color shooting materials. Further, with a recent reduction in format as employed in the APS, improvement in image quality also becomes more important than hitherto, so that color negative type shooting materials high in sensitivity and image quality have been eagerly desired.
On the other hand, the spread of lens-mounted film (film with lens) is remarkable, and smallness in size, lightness in weight and simple operation thereof have been supported by consumers. In the case of lens-mounted films, the insufficient quantity of light of electronic flushes particularly introduces a problem because of restrictions of smallness in size and low cost. It has been therefore a very important problem to increase the sensitivity of shooting light-sensitive materials.
For the lens-mounted films having no diaphragm mechanisms, however, the increased sensitivity of shooting light-sensitive materials results in too much exposure under the snow mountain or fine weather conditions in summer, which causes too high density of color negative films of the shooting light-sensitive materials. Accordingly, printing with an automatic printer takes a tremendous period of time. Alternatively, the density exceeds the reading density range of a CCD, so that it can not be read even by a digital printer. As described above, the serious problems have become clear.
For solving these problems, various lens-mounted films having diaphragm mechanisms have been devised. However, they can not be actually used, because they increase costs and impair the simplicity of operation.
Further, a method is also considered in which the gradation of shooting light-sensitive materials is softened to prevent the negative density from increasing too high even by shooting under high illumination. However, in such light-sensitive materials, the contrast becomes extremely low by shooting under normal or low illumination, which introduces a serious problem.
Furthermore, a process of reading the above-mentioned soft (low contrast) light-sensitive materials using a scanner mounted on a digital printer, and treating digitalized signals to adjust the contrast properly has also recently been proposed. However, when this process is actually performed, the granularity is significantly deteriorated at the stage that the contrast is emphasized by image processing, and particularly, a region decreased in exposure does not stand practical use.